A smart home device alerted authorities to an alleged assault at a residence in New Mexico earlier this week.

Eduardo Barros was house-sitting with his girlfriend and her daughter Sunday night at a residence in Tijeras, some 15 miles east of Albuquerque. The couple got into an argument and the altercation became physical, according to the Bernalillo County Sheriff Department’s spokesperson, Deputy Felicia Romero.

Barros allegedly wielded a firearm and threatened to kill his girlfriend, asking her: “Did you call the sheriffs?” A smart speaker, which was hooked up to a surround sound system inside the home, recognized that as a voice command and called 911, Romero said.